


The Great Swinger Conspiracy

by Tynytyg



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: And their wives being like "no shit dumbass", But mostly this is about Dimitri acknowledging that he's been in love with Felix most of their lives, Bylix are really casual about extramarital sex, Dimitri is kinda stunned, F/F, F/M, Happy marriages?, I haven't written porn in a million years, If You Squint - Freeform, M/M, Marianne is totally into it, Multi, Oh both sets have kids that are very briefly mentioned, Porn with Feelings, Swingers, There's sort of a plot, and then they bang, don't look at me, it's great
Language: English
Status: Completed
Published: 2020-07-24
Updated: 2020-07-24
Packaged: 2021-03-04 20:47:58
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 7,869
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25482667
Author URL: https://archiveofourown.org/users/Tynytyg/pseuds/Tynytyg
Summary: “Hold on, don’t freak out,” she tells him. He quiets, concentrates on controlling his breathing, and waits for further instructions. “We’re not trying to tell you anything in code, I’m genuinely asking because I want to know. The rumors about Felix and me are true, and I’m wondering if you’d be open to fucking him. While Marianne and I watch, of course.”This brings Dimitri to a screeching halt.Would he be open.To fucking Felix.
Relationships: Dimitri Alexandre Blaiddyd/Felix Hugo Fraldarius, Dimitri Alexandre Blaiddyd/Marianne von Edmund, Felix Hugo Fraldarius/My Unit | Byleth, Marianne von Edmund/My Unit | Byleth
Comments: 5
Kudos: 56





	The Great Swinger Conspiracy

**Author's Note:**

> Yeah this is just my attempt to get back in the smut writing game, please don't make eye contact with me, I might combust  
> My lovely beta Azurite9925 continues to be the only reason I function as a human

Byleth’s serious face is always intimidating, but when she’s dressed in her full Archbishop’s regalia, she really is something else. Dimitri is the Savior King of Fodlan, the winner of a long and grueling war, and survivor of his own troubled past. He really shouldn’t be this concerned by the sight of his wife and his onetime professor sitting in his parlor together, having tea. Marianne looks up and smiles at him, the warmth and gentleness of that smile still something he cherishes each time. Byleth looks up too, and Dimitri suddenly worries that there’s been some sort of uprising or revolt somewhere. She’s become more expressive since she married Felix and started having babies, but she’ll never be easy to read. 

“Archbishop,” he greets her formally, because they’re both still dressed for their official titles. “What a pleasure to see you again. I didn’t know you were in Fhirdiad.” 

She quirks a tiny smile at him, and he relaxes marginally. She doesn’t smile when she’s here with truly terrible news. “Your Majesty.”

“Please,” Marianne says sweetly, sipping her tea. “Let’s not be so formal.”

“Alright,” Byleth responds, and stands up to unhook her collar ruff and cloak. She peels them off and drapes the ornamental clothing over an unoccupied chair, then sits back down and looks expectantly at Marianne, who laughs. 

“Much better, Professor,” Marianne approves. “Now you, Dimitri.”

Feeling like he’s missed something, Dimitri sets his crown on a table and hangs his cloak on the rack by the door. He comes and sits when Marianne beckons, and takes a little cake and a cup. “To what do we owe the pleasure, Professor?” He asks. “Is Felix in town as well?”

A strange smirk curves Byleth’s lips as she replies, “Yes. He’s… a bit tied up right now, doing a favor for me.”

Marianne giggles. Dimitri sips his tea, mystified. 

“I actually came by the palace to ask you something, Dimitri.”

He perks up. He’s always happy to do anything for the church, and even happier to help out his old teacher. Most of her students still can’t bring themselves to call her by her name, which seems to amuse more than irritate her, but Dimitri counts himself lucky that he’s had enough exposure to her to be able to respond, “Of course, Byleth. Whatever you need.”

“I’ve been talking to Marianne about it,” she says, and Marianne nods confirmation, “so you don’t have to worry on that front. And since I’m asking, you know I’m alright with it. But don’t feel pressured to say yes if you don’t want to, because no one will judge you for your response to this question.”

Dimitri is still confused, but this is quite a long speech for Byleth, so he waits. He’s sure she’ll come to the point eventually. 

“You’ve probably heard the rumors about Felix and my… habits.” 

He has indeed heard the stories, passed from servants to stablehands to innkeepers and eventually to the ears of even the king, of Duke and Duchess Fraldarius’s tradition of crossing swords every time they were reunited. Perhaps she wanted to train? Though she of all people should be confident in her skills; she’s kept in far better shape than he has since the war. And why would she need to ask Marianne about that?

“I’m pretty sure of my analysis, but I have to check–you did have a crush on Felix, before the whole world went to hell, right?”

Dimitri chokes on his tea. 

He sets the cup down a little too hard, which cracks the saucer and sends tea sloshing out onto the finely woven table cloth, and he’s still coughing up a lung trying to breathe. Byleth springs out of her seat and comes over to pound him on the back, while Marianne grabs her napkin and begins dabbing up the tea, watching him with concerned blue eyes. 

When he can speak again, Dimitri chokes out, “What gave you that impression?”

Byleth eases back into her chair, and Marianne picks up the broken saucer and sets it to the side. The palace’s head housekeeper had long ago despaired of keeping the King in fine china, and now the tea sets he and Marianne use in private are plain and easily replaceable, but that doesn’t make it any less embarrassing when he breaks something. He takes a deep breath and waits for an answer.

“Well,” Byleth says slowly, as if she’s martialling her reasons on the spot. “You spent quite a lot of time together, despite how much he said he hated you. And whenever he would spit in your face and run off, you watched him go with this look on your face like the whole world was walking away with him. And once or twice, when I was on night patrol and walked past your rooms–”

“That’s quite enough evidence,” Dimitri interrupts with a nervous glance at Marianne, who hides whatever reaction she’s having behind a teacake. “I may have harbored some… feelings, back then. Long abandoned, of course. I am happy in my marriage.”

“Oh, I don’t doubt that,” Byleth waves a dismissive hand, as if what Dimitri just admitted wouldn’t have ruined some relationships. “I was just wondering if you still think him physically attractive.”

Dimitri sputters, until Marianne looks up with a slightly impish expression in her eyes, and murmurs, “I certainly do.” 

This does not diminish the sputtering, but it does change the tone. Is she suggesting that Dimitri isn’t her ‘type’, as Sylvain would phrase it? Does his wife not feel attracted to him anymore? He begins to dissolve into a panic, but Byleth’s firm voice stops him before he can really get started. The same voice that guided him through battle and gore and horror now guides him through this extremely strange conversation. 

“Hold on, don’t freak out,” she tells him. He quiets, concentrates on controlling his breathing, and waits for further instructions. “We’re not trying to tell you anything in code, I’m genuinely asking because I want to know. The rumors about Felix and me are true, and I’m wondering if you’d be open to fucking him. While Marianne and I watch, of course.”

This brings Dimitri to a screeching halt. 

Would he be open. 

To fucking _Felix_. 

His mind leaps back almost fifteen years to his days as a hormonal, emotionally disturbed teenager. To all the nights he’d spent lying between sweat-soaked sheets, staring at the ceiling, rutting into his own hand, thinking of flashing amber eyes, dark hair, and a very specific voice saying harsh things. All the times the fantasy of the boy in his bed had stopped cursing at him, had whispered secret desires, wanting to be held down, fucked open, pleasured until the only thing he could say was _Dimitri, Dimitri, Dimi-_

“Dimitri? Are you okay?” Marianne’s hand is on his arm, and she’s looking at him with concern. Byleth, still in her seat, is munching on a cake as if this is a normal thing to ask a married, theoretically straight man. Who also happens to be king. In the presence of his queen.

“I’m… fine. Thank you, Marianne.” Dimitri manages after another long second. 

She sits back down, but she doesn’t seem like she believes him. Byleth finishes her cake, washes it down with tea. Her hands disappear into her robes, and she looks at him with her usual neutral expression. Waiting. Waiting for an answer to her question. 

He looks at his wife. “You’ve… already spoken about this?” His voice is still strained, but it sounds a little more normal than a moment ago. 

She nods, almost shyly. “I think it would be good for both of you.”

Good for both of them. Another part of Byleth’s question catches at Dimitri’s mind, derailing him. “Wait, what did you mean about rumors?” He asks his professor.

Byleth quirks a smile at him. “Have you really not heard? I thought Sylvain would’ve told you for sure. Felix and I… sometimes invite others to bed with us. There’ve been quite a few, over the years. That kind of thing gets around, even with only the most discreet servants and partners. I assumed our reputation was well-established.”

“No,” Dimitri shakes his head, still a little stunned by the enormity of the situation he’s landed in. “No, I hadn’t heard.” Another concern occurs to him. “Is that… safe? If the paternity of the heirs to the Fraldarius dukedom comes into question, that could cause-”

“We’re very careful,” Byleth cuts him off. “And anyway, I’m the archbishop. I’m the final arbiter of any disputes about inheritances if nobody thinks to ask you first, so I get to decide. Also, tell me Rodrigue and Sitri don’t look exactly like their father.”

Marianne laughs at that, a bright little sound, and shakes her head. “We can’t. Your children look like the Goddess took your best features and Felix’s and mixed them together. It’s really quite uncanny.”

Dimitri nods agreement. “True.” He inhales, and takes the plunge. “I’m not against the idea. It’s just a little… startling.” 

Byleth hums, removes one hand from her robes, and sips her tea. “That’s about what Dedue said.”

He almost chokes again, then demands, “Dedue? And Ashe agreed to that?”

She grins back at him over the rim of her cup. “It took some convincing.”

“It must’ve,” Marianne marvels, no doubt thinking of the time, right after the war ended and the pair opened up their inn, when Dimitri had been required to personally visit and settle a dispute between Ashe and a man he’d apparently thrown out in the snow for flirting with his husband. Or the time Dedue had physically pinned an ex-Empire noble to the wall of the inn by his throat for grabbing Ashe’s rear end as he passed by. Or the time Ashe had a party of Almyran dignitaries escorted under guard out of Castle Gaspard because the woman leading said party had tried to kiss Dedue in a corridor. Or the time– 

Needless to say, those two seem a particularly unlikely prospect for extramarital endeavors, no matter who they’re with. 

“Is it too invasive of me to request a… an accounting of the people with whom you’ve..?” Dimitri leaves it hanging, torn between intense curiosity and absolute horror. 

Byleth giggles– _giggles_ –and nods. “No, it’s understandable. Let’s see, there was Seteth, fairly early.” Marianne makes a shocked noise, and Byleth grins at her. “What? I was curious! In case you’re wondering, yes, he is in fact green all over.” Dimitri had not been wondering, but now felt certain he’d be thinking of that every time he looked at Byleth’s chief advisor. 

“Then there was Sylvain and Mercedes, but that’s sort of a given. Ashe and Dedue I already told you about. Claude and Hilda, though that one is a bit more difficult now that they’re not attending diplomatic summits here or in Derdriu every few months. Ferdinand and Dorothea, when they’re in Fhirdiad for her performances. Lorenz, exactly once. He still won’t write directly to Felix, he sends all his messages through me. I think it’s because he wants to try again, he just can’t unbend enough to ask. Anyway, then there was that memorable time with Yuri and the crew…” She trails off, apparently lost in thought.

"What, all four of them?” Dimitri asks, shaken. “How does that even–” he abruptly decides he doesn’t want to know, and stops. 

Byleth just raises one eyebrow, and Marianne presses a napkin to her own lips to stifle a giggle. “Oh, and Leonie and Ignatz, the last time they passed through. That should be all of them, unless I’m forgetting someone. I shouldn’t be, I keep fairly close track.”

Dimitri briefly imagines a world in which he’s had sex with enough people to be in danger of forgetting some. Then he looks at Marianne and quashes that thought. He isn’t interested in that kind of life anyway. He loves his wife. He’s just shocked by the idea that _Felix_ apparently lives like this. He’d expected his oldest friend to be the jealous and possessive type. 

“So,” Byleth prompts after a few more moments of dazed silence. “Still interested in fucking Felix, or should I go take care of him before he gets loose and comes looking for me?”

“What?” Dimitri feels like an echoing cave, repeating himself endlessly. He must be dreaming, because it had sounded like Byleth meant– 

“He’s bound and gagged in our rooms down the hall,” Byleth informs him casually. “And he’s a devil about getting out of ropes when he gets frustrated, so I really overdid it with the knots this time. He’s been in there for almost an hour now, so he’s likely to have at least one arm free pretty soon. Plus, I’ve been messing with him the whole time we’ve been talking.” She pulls the hand that’s been buried in her robes out, and with it comes a small black box inscribed with shifting runes. They glow mint green, like her hair, and when she closes her hand over the box, it vibrates. 

Dimitri doesn’t know what that means, but Marianne gasps quietly and turns pink. He looks at her questioningly, but she won’t meet his gaze. Byleth watches this interplay, merriment dancing in her eyes. “Your wife knows what this is,” she teases.

“Marianne?” Dimitri asks, worried by her silence

“It’s ah…” She hesitates, cheeks still rosy and not meeting anyone’s eyes. “A bit of sympathetic magic. The runework on the box makes it shake when you close your hands, and when it vibrates, so does something else… usually, um…” 

Byleth takes over before Marianne combusts from the intensity of her blush. “In this case, it’s a plug, about this big.” She makes an estimate with one hand. Marianne’s eyes widen. Dimitri has no idea what use one would have for a plug that vibrates, and at this point he’s not entirely sure he wants to know. Still, he asks. 

“And where is that, right now?”

“Felix’s ass.” 

Dimitri takes a moment to collect himself. He keeps himself in the present, in this room, on the fragile teacup he’s still holding in one hand. If he doesn’t concentrate, he’ll be thinking about Felix, tied to the heavy four-poster bed in the suite of rooms that had belonged to the Fraldarius family for decades, something _about an inch and a half in diameter_ holding him open, _buzzing_ as Byleth closes her hand on the black box. The way he probably looks, flushed and squirming, panting, mouth hanging open slightly as he… 

“Dimitri, are you still with us?” Byleth interrupts, a tiny smirk playing about her lips. Dimitri realizes with a flash that she did that on purpose. He’s astonished, slightly irritated, and deeply impressed at her ability to send his mind directly into the gutter. 

He very gently places his teacup back on the table and resolves not to pick it up again until he’s certain Byleth is done shattering his barriers against various horny fantasies for the evening. At least Marianne isn’t still looking at him with that worried furrow in her brow. Now she’s smiling at him from behind another cake, and he’s not really sure it’s an improvement. 

When he’s got himself mostly under control, he takes the plunge. “Let’s go check on Felix.”

Byleth is too stoic and Marianne is too naturally quiet to cheer, but Dimitri can see the victorious gleam in their eyes. The Archbishop stands, brushes the cake crumbs brusquely off her gown–she never did learn how to eat like a lady, as opposed to a mercenary–and offers Dimitri the vibrating black box. He stands as well, and takes it. 

“You just close your hand on it to make it start,” Byleth instructs. “If you squeeze it, the speed picks up.”

Marianne comes over to look at the box, eyes tracing the elaborate runes. “That’s a very pretty piece of magic,” she comments. “How much did it cost?”

Byleth rolls her eyes. “Felix wouldn’t tell me. He has the weirdest hangups. Ask Constance, though, she made the thing. Actually,” she corrects herself, “Yuri’s probably a better source. I know he’s selling them for her. He probably has the most up to date prices.” Marianne nods, mulling it over, and Dimitri curiously closes his hand. 

The box buzzes to life, and he almost drops it, startled despite himself. He squeezes, and indeed, the buzzing intensifies. He opens his hand again, and it stills. Fascinating thing. Dimitri wonders why Marianne had asked. Maybe it’s a complicated magical trick, and she’s interested academically. Since they’d settled down, she’d become more and more involved in white magical research. That must be it. 

Byleth leads the whole party out of the royal quarters and down the hall, to the Fraldarius suite. It’s not far, close enough for two friends to walk over and converse at any hour of the day or night. Or, close enough for a tryst or two. There’s records of such, in the Blaiddyd family’s collection of diaries, journals, and other personal writings. It’s been tradition to pass down the stewardship of that collection from king to king for centuries, and Dimitri’d been more than surprised to discover how _candid_ some of his predecessors had been with their semi-private journals. His own usually held only his poor attempts at love poetry and the occasional midnight thought he wanted to remember in the morning. 

Through the door to the suite, then another, into the bedroom. And there Felix is, laid out on the bed. Dimitri stops in the doorway, to drink in the sight. 

Felix is on his back, arms over his head, wrists wrapped in black cord. The way the silky material stands out against Felix’s pale skin is stark, highlighting the slight pinkness where he’s chafed himself struggling. His head is thrown back and his lips are stretched around something ovoid, strapped in place with leather, eyes squeezed shut and tears pricking at the corners. 

His chest is flushed, heaving, criss-crossed with the weave of the restraints. Felix’s legs are bound apart, ankles attached by more of that soft looking black rope to the bottom posts of the bed, preventing him from getting any leverage at all. Between them, his dick curves upwards to where it leaves a smear of precome on his toned stomach, and below that… Dimitri closes his hand on the box, and the plug buzzes in time with it. Felix groans, low in the back of his throat, and Dimitri _burns._ He opens his hand again, looking to Byleth for guidance.

Byleth crosses the room to where Felix lies and, seemingly heedless of her guests, takes his dick in one hand and strokes him from base to tip. With her other hand, she methodically works the gag loose from his mouth. His eyes fly open and he squirms, then spits a particularly vile curse at her, in Almyran of all things. Dimitri’s heat-dazed brain provides the translation as something along the lines of “may the evil gods rot your intestines.”

Byleth takes her hand off Felix’s dick and slaps him hard across the face without changing expressions.

“Sorry,” their hostess says over her shoulder, apparently mostly to Marianne. “He’s picked up some bad habits from Claude.” To Felix, she says, “Now love, is that any way to talk when there’s a lady present?” 

And she sounds for all the world as if she’s scolding a recalcitrant child or an unruly pet. 

“Thankfully,” she continues to Marianne and Dimitri, “Hilda taught me some ways to handle this type of behavior. Dimitri, will you do me a favor and squeeze that box for me?”

Felix’s eyes widen as he realizes who’s in the doorway and what Dimitri’s holding, and his body arches when Dimitri obediently closes his hand. A whimpering moan tears itself out of Felix’s throat, and he thrusts up into the air as if seeking some sort of relief. Dimitri squeezes like Byleth instructed, and Felix cries out, already sounding wrecked. 

“That’s enough,” Byleth releases them both. Dimitri opens his hand, and Felix slumps back against the bed, panting. “You know you won’t get to come until you learn to be polite,” Byleth chides her husband. “Now greet our guests like a reasonable person.” 

Felix rolls his head away, unable to look at them as he grits out, “Good evening Marianne. Dimitri.” His voice sounds like heaven, exactly like it had in all Dimitri’s most filthy teenage fantasies, low and rough and biting. 

“See, was that so hard?” Byleth asks lightly, patting him on the cheek. “Come in and sit down, both of you.” She gestures magnanimously to the chairs set up to one side of the bed, and the King and Queen of Fodlan sink into them like the obedient school children they’d been, once upon a time. Byleth straightens from where she’d been bent over Felix, and begins undressing, peeling out of her layers of robes as she speaks. 

“So, there’s a few easy-to-remember rules. Felix is a brat, so if he’s rude to you, either you hit him or I will. We have to instill good manners. This doesn’t come off until I say so.” She points to something Dimitri hadn’t noticed at first, too focused on the plug in Felix’s ass. It’s a slim metal ring, fitted snugly at the base of Felix’s dick. Dimitri isn’t sure it’s purpose, but he’s sure he’s about to find out. “It’s to keep him from finishing without us, you see.” 

_Oh, Goddess._

“If you’re ever uncomfortable in any way, you tell me and we’ll stop, no judgement,” Byleth continues. “The same goes for Felix, which of course he knows.” The man in question flips her off with one of his bound hands. “I love you too. Are there any questions?”

Dimitri marvels. She’d asked “are there any questions” after every lecture, seminar, and war meeting she’d ever led in exactly that tone of voice. Brisk, competent, and inviting. How she can maintain such a level head in the presence of someone writhing on a vibrating plug, Dimitri has no idea. Just to see what happens, he squeezes the box again. Another groan rises from the bed behind her, but Byleth doesn’t flinch. 

“No questions,” Marianne responds, voice still sweet and showing no sign of the hunger in her eyes. She’s watching Felix with a predatory gaze, the same one she turns on Dimitri when he returns from long diplomatic missions abroad without her, or when he comes in still sweaty from training, or when- but he’s getting distracted. 

Now her eyes are on Felix, and it’s surprisingly hot to see that look aimed at someone else. In profile, the delicate lines of her features are picked out to best effect, and Dimitri is suddenly overwhelmed with the urge to kiss her. 

Seeing no reason to fight this urge, he puts two fingers under her chin and turns her to look at him, tipping her face up. Marianne moves easily, and the desire on her face changes targets. She leans up into his touch and devours him in a kiss. Byleth makes an approving sound from her position closer to the bed, and Dimitri hears the rustle of cloth as she divests herself of her robes entirely. Marianne breaks the kiss to look, and something hot and possessive flares in him at the way his wife’s breath gusts out of her. 

He looks too, and abruptly understands. 

Byleth stands by the bed wearing a light shift that clings to her body, and obviously nothing else. Her nipples are hard peaks beneath the silky, translucent material, catching at the fabric as she turns to lean over Felix. It whispers over the skin of her waist, her legs, her backside, accentuating the curves and planes of her body. Strong thighs, flat stomach, an ass that makes Dimitri want to leave hand-print bruises. She glances over her shoulder at them and smirks, a tiny curling of the lips, and wraps one hand around Felix’s dick again, which makes him gasp. 

“Dimitri, come here.” 

He’s out of his seat and halfway to Byleth before the command even fully registers, and he briefly imagines he should be at least a little ashamed of how quickly he responds to her. Then he pushes it aside. Listening to her has always felt easy, felt _right_. Why should it be any different in this setting? She looks up at him and the small smile playing about her lips makes him feel like he’s won something. 

“Good boy.” 

This sends a Thoron bolt directly to Dimitri’s dick, and _wow,_ he didn’t know it about himself until now, but those words are apparently an enormous turn on. He hopes Marianne is taking notes, because if she can help him replicate this feeling he’ll never let them leave their rooms again. Byleth takes his hand, places it on Felix’s hip. 

Felix shudders, head tipped forwards to watch as Dimitri runs his hand up and over pale skin, scarred here and there with old battle wounds. A particularly nasty gash in the side that Felix had sustained protecting Dimitri during their academy days stops him, and Dimitri strokes two fingers along the full length of it. He wants to kiss the spot, press his lips to the affirmation that his oldest friend and longest-held fantasy was really here, alive, shivering beneath his hands. He looks at Byleth. 

“May I-?” He hears the roughness in his voice, realizes how tight his trousers have become just from this little bit of contact. 

Byleth nods, taking the black box out of Dimitri’s other hand to free it, and steps back from the bed. He kneels beside the mattress, reverently laying kisses along the scar. Felix sucks in a breath at the first press of lips to skin, and Dimitri’s still half-convinced this is a dream until he feels the way Felix’s chest moves beneath his mouth. He kisses along the line of Felix’s ribs, up to one nipple, and very gently presses his lips there. Felix _writhes_ , fighting the bindings, searching for _something._

“Get on with it, boar,” he rasps, and Dimitri looks up to find Felix’s amber eyes fixed on him. They’re burning with intensity, and the old insult goes straight to Dimitri’s dick. Once, it had hurt. Now it just calls up all those long-buried fantasies from when he was seventeen, of Felix cursing him while sitting on his cock. 

“Dimitri, remember the rule?” Byleth asks from somewhere behind him.

“Fuck,” Felix says. Marianne giggles helplessly. 

“If he’s rude to you,” Byleth coaxes.

“Either I hit him or you do,” Dimitri finishes, reminded. “Do you have a preference?” He looks over his shoulder and finds Byleth on her knees before Marianne, his wife’s skirts rucked up to her waist, a rosy flush staining her cheeks. He wishes he could keep the image forever, of Marianne’s hands white-knuckled on the arms of the chair as Byleth kisses and nips her way up one thigh. She pauses in her path and smiles at Dimitri. 

“I think he’d like it very much if you would,” she informs him breathily. Apparently she’s _not_ completely unaffected by the business taking place in this room. 

“I don’t want to hurt him,” Dimitri demurs. Byleth laughs. It’s a mean little sound, and Felix twitches beneath his hands.

“Fuck,” Felix repeats, sounding hopelessly turned on. “Please, Byleth.”

She seems to understand what he means, because she abandons Marianne–who emits a small, deprived sound–to get up and guide Dimitri. She takes his hand in hers, lifts it from Felix’s chest to his neck, and presses down gently. Felix snarls another curse at her, and she lifts a hand in threat. He eyes it warily, settling back into his bonds. Dimitri’s palm is still on his throat. “Gentle, here. Anywhere else, I think your strength is more attractive than intimidating.” 

“What if I-”

“Dimitri, I’m here,” Marianne interjects for the first time this evening. “You have a professional healer in the room with you. I’ll fix him if you overdo it.”

With this reassurance, Dimitri relaxes a little. He takes his hand away from Felix for a moment, then runs his fingers down the center of his sternum. Down over his stomach, then across to his hip, then delicately drags just the tips over one tense thigh. Felix squirms at the tickling sensation, and then, while Byleth watches, Dimitri brings one large hand down firmly on Felix’s thigh. 

The smacking sound rings through the room, and Felix jerks, biting off another curse. 

Byleth hums approval and returns to Marianne. A soft sigh comes from behind him, and Dimitri knows his wife is being taken care of. He can focus on Felix, which is doubtless Byleth’s intention. He spares a moment to adjust his trousers, uncomfortable in their confines, and Felix’s burning amber gaze tracks over to the tightness Dimitri is trying to alleviate. His tongue darts out, wetting his lips. Dimitri bites back a groan. 

“Go on,” Felix murmurs. “Take them off.”

Dimitri has rarely been naked in the presence of anyone but Marianne since the end of the war, but he remembers the bathing arrangements at Garegg Mach. The way he’d scolded Sylvain for checking out anyone and everyone, the way he’d occasionally caught Ashe and Dedue’s eyes lingering on one another. He’d convinced himself at the time that he was imagining Felix’s fixation on the other men in the baths or the sauna. It was just wishful thinking that Felix seemed more interested in the taller ones among them, in Balthus, Dedue, and himself. Now, he curses his younger self for ignoring the signs, and unbuttons his pants to slide them off.

He kicks out of his boots and lets his trousers and smallclothes pool on the floor, then peels off his shirt for good measure. When he’s done, Dimitri puts a knee up on the bed and looks at Felix for confirmation that it’s okay. Felix isn’t looking at his face, however, eyes fixed somewhat lower. His mouth hangs slightly open and his breath comes faster, pupils blown out so that black almost completely swallows that distinctive flame amber.

“Fuck.” he says, for a third time. A full-throated laugh comes from the chairs behind Dimitri, and he realizes with a start that it’s Marianne.

“I know,” she says, the laughter still in her voice. 

Dimitri shifts, bashful. He knows he’s rather well-endowed, but to be openly appreciated like this is still a little embarrassing. Nevertheless, he climbs up onto the bed. The mattress dips under his weight and Felix slides marginally closer, but the ropes hold him in the center. Dimitri situates himself between Felix’s legs before leaning forwards to plant one hand next to his head. This position puts his dick over Felix’s stomach, Felix’s against one of Dimitri’s thighs. Felix looks up at him and smirks, an expression which disappears into a moan as he grinds against Dimitri’s leg. Dimitri is fairly certain that’s not a thing Byleth would allow Felix to do, but doesn’t know what she’d do about it, so he settles for placing his other hand in the center of Felix’s chest, fingers spread. 

“Are you going to do anything, or just sit there like a besotted fool?” Felix asks, voice rough, and Dimitri slides his hand up to pinch one nipple. Felix groans, but he doesn’t stop talking. “If it takes you this long to get started, it’s no wonder you’ve only got the one child.”

Dimitri’s hand snaps to Felix’s neck, and it fits against his thundering pulse like it is made to be there. Felix abruptly relaxes, eyes going wider before fluttering shut, expression immensely peaceful. His dick twitches, but the rest of his body melts into Dimitri’s touch, pliant and wanting. Dimitri has to stifle a groan of his own as all the fight goes out of the man beneath him. 

Complete submission, achieved as easily as that. 

“Well that’s new,” Byleth murmurs in a tone usually reserved by normal people for particularly interesting chess strategies. It is the same voice she’d used during the war to inform her students of incoming enemy battalions, ambushes, and the daring combat maneuvers which had won battle after battle. Dimitri had dubbed it her Tactics Voice, back then. It’s interesting to hear it in this context, with his hand on Felix’s throat, Felix quiescent beneath it, eyes shut and breathing quietly. “He’s never submitted like that for anyone else. Your relationship is so strange, you know that?”

Dimitri finds himself huffing a laugh, nodding. “Yes. It really is.” He gives himself a moment, reveling in the calm he can apparently bestow on Felix with a touch. Mentally filing that information away for the next time Felix is too keyed up to sleep and Byleth isn’t around, Dimitri lifts his hand. Felix’s eyes open, but he doesn’t begin mouthing off again. That deserves some sort of reward, so Dimitri leans down and kisses him. Gently. Like he’s made of crystal, and might shatter with an incautious touch. 

Felix trembles, but kisses him back with equal gentleness. Then, he deepens the kiss, drinks Dimitri in. Dimitri finds himself falling into it, the moment of peace abandoned in favor of the building heat in his core. He reaches down and grabs Felix’s hips, stilling them where they’ve begun to grind against him again. When they break apart for air, Dimitri asks, his lips still brushing Felix’s, “Would you like my cock, Felix?”

He meets Dimitri’s eye, looking like a starving man offered a five course meal. “Yes,” he breathes, and all of Dimitri’s fevered fantasies could never compare to the spike of heat that rushes through him at that one word. 

“How do we ask?” Byleth inquires archly from somewhere in another universe, and Felix makes a face. 

“Please,” he adds grudgingly, and it breaks Dimitri’s resolve to be gentle. He reaches down to press his fingers lightly against the end of the plug, and Felix whines. He toys with it for a moment, not out of a desire to tease but because he’s not sure what to do. “Take it out,” Felix pants, “and use your fingers.”

Dimitri obliges, tugging the thing loose. He discovers that it’s several inches long, and slicked with something that smells vaguely of mint. Watching Felix’s hole clench around nothing is fascinating, but a whiny sound from Felix gets Dimitri moving. He sets the toy on the bedside table and presses one finger against the pucker. He’s never done this before, but he’s heard Sylvain talk about it enough to last three lifetimes, so with a single smooth motion, he sinks his index finger in to the second knuckle. Felix makes a sound like he’s been punched, and his hole clamps down around the digit. 

Worried he’s hurt him, Dimitri looks up to Felix’s face. Felix’s head is tipped back again, bottom lip between his teeth, chest heaving. “More,” he demands roughly. Dimitri gives it to him. He’s still slick with whatever Byleth had used to ease the way for the plug, and the rest of one finger slides in. Dimitri begins to pump it in and out, which Felix seems to like because he’s groaning softly with every exhale. 

“More,” he says again, and Dimitri withdraws his finger entirely. Felix whines at him, but Dimitri understands this process well enough to know he needs more lubrication. 

“Byleth, where’s the-”

“Top drawer,” she answers. “It’s the clear vial.”

Dimitri spares a glance for the girls, and abruptly wishes he hadn’t as all the blood in his brain shoots southwards. Marianne is naked and sprawled in one of the chairs, Byleth straddling her, one hand moving between them. There are little mouth-shaped bruises all up the insides of Marianne’s thighs, and her hair is down out of its braids, falling freely around her face. Her eyes are closed, head tipped back as Byleth sucks another bruise into her collarbone. She looks radiant, and possessiveness flares in Dimitri again. He wants to cross the room, pull Byleth off her lap, and satisfy her the way he knows he can. However… 

A tiny, whimpering moan escapes her lips, and when she lifts her head and opens her eyes to look back at him she seems triumphant. Like the fact that the Archbishop of Fodlan and the Savior King are both interested in her pleasure is a victory she’s won, and they’re all just doing her bidding. It’s an incredibly sexy thought. 

Felix jerks his hip up into Dimitri’s leg, effectively getting his attention again, and Marianne grins as she closes her eyes. 

Dimitri yanks open the top drawer of the dresser and finds the vial, opens it, and returns to his task. He pours some over his hand and presses his fingers back to Felix’s hole before it occurs to him that the temperature might be uncomfortable. Felix twitches, but the look he sends Dimitri implies murder if he stops. The press of two fingers is more difficult, though the plug seems to have done its job well. Dimitri takes a chance that some things are the same between men and women and hooks his fingers, which draws a gasping moan out of Felix. Felix’s neglected dick lies against his stomach, flushed and weeping precome. Dimitri takes it in his other hand, and Felix’s whole body spasms. 

“More, please,” he gasps. “Dimitri, I need-”

“I’ve got you,” Dimitri replies, breath ghosting over Felix’s lips before he kisses him again, adding a third finger. Felix whimpers, trying to grind down on Dimitri’s fingers. Dimitri increases the force with which he presses inside, keeping a slow pace but making sure every stroke hits that spot that makes Felix shake. 

Felix breaks the kiss to glare up at him, frustrated tears beginning to fill his amber eyes. “Dima,” he pleads. “Give me your cock. I need it. Please.”

Dimitri, to put it politely, loses his shit. A growl tears itself out of his throat, and he pulls his fingers free of Felix’s ass perhaps too quickly. He’s immediately shifting to line himself up, and the wince on Felix’s face is replaced with blissed-out shock. The way eased by careful preparation and more of the startlingly cold liquid from the vial, Dimitri presses his tip inside, and the pressure almost overwhelms him. Felix clamps down around even that much, greedily sucking him in. Dimitri struggles for control, but Felix is still begging, pleading with him for _more, faster, now,_ **_please_ ** and can Dimitri really be expected to hold out against that? 

He sinks into hot, vice-like heaven, and Felix _moans_. 

With Marianne, Dimitri is always careful, always sure to ask if she’s comfortable, to move slowly and do his best not to hurt her. Sometimes she protests his excess of care, but they both know it’s because he loves her and never wants to cause her any pain. And because he is, well, rather larger than average. In every aspect. So he’s careful, even when it takes all he has to keep his pace slow at first, to rock gently into the embrace of her body and to work her up to the quicker, rougher way she prefers to be fucked. She always helps, hands on his hips and whispering encouragement, guiding him through the first four or five thrusts when he’s most likely to snap and go too hard too early. 

Felix, a litany of curse words, pleas, and endearments spilling off his tongue, bound and begging for Dimitri to pound him into the bed, isn’t doing much for his self control. Dimitri’s fingertips press hard into his bony hips, and Felix grinds himself down, using his white-knuckled grip on the ropes above his head for leverage. 

“Dima, Dima, please,” he chants, voice wrecked. “Move, I need you to-” Dimitri moves, pulling out of that incredible pressure almost completely before pushing all the way back in with one long motion. Felix’s voice breaks on a groan and a tear spills down his cheek. Before he can think, Dimitri’s fucking into Felix with the same pace as his fingers had been. Felix’s breath hitches with every thrust, dick bobbing between them until Dimitri wraps one large hand around it, pumping it in time. 

When Dimitri touches him, Felix gasps his name, and the blissed-out look on his face is almost enough to have Dimitri coming right there. But he wants this to last, wants to make Felix feel as good as he does. So he changes his angle, looking for that bundle of nerves that will make him see stars. A few experimental thrusts in, he finds it, and Felix sobs. Dimitri groans as the pressure around him somehow intensifies, and tightens his grip. Felix can't seem to decide whether to push back down against Dimitri’s hips or up into his hand, and the sounds he’s making… 

_Goddess,_ Dimitri thinks, _no fantasy could’ve ever compared._

Suddenly, Marianne is beside him, small hands stroking up his sides and down his back as he moves, murmuring encouragement and telling him how good he looks, how well Felix is taking him. Byleth appears on his other side, tweaking Felix’s nipples and smiling cruelly. 

“Do you think he deserves to come, Dimitri?” She asks, and he slows his pace, momentarily confused. That had been his goal, yes. What was she…? Then he remembers the ring around Felix’s cock, and sucks in a sharp breath of his own. 

“ _Please_ ,” Felix keens. “I’ve waited for hours, and I feel so full, please let me-”

“Yes, Professor, of course, he’s been so good for me,” Dimitri babbles, instinctively trying to communicate how _much_ he feels all at once. 

Byleth huffs a low laugh and nods. “Alright.” She knocks Dimitri’s hand away from Felix’s dick, then gently tugs the ring off. It takes two more thrusts before Felix is crying out, throwing his head back, and spilling over his own stomach. He tightens impossibly around Dimitri, and Marianne runs her fingers up into Dimitri’s hair, tugs lightly, and whispers in his ear. 

“Your turn, beloved. Come for us.” It’s the _us_ that does it, he thinks later, when he regains the ability to think. For now, a white roar fills his head and he comes, pleasure blanking out the rest of the world except for the tight heat around him, Marianne’s hand in his hair, and Byleth’s intense, sea-green eyes watching him come undone.

When he can see well enough to be sure he won’t crush anyone, he pulls out carefully and flops down beside Felix. Dimitri knows he’s fairly useless for a period after he’s climaxed, so he worries about taking care of his partner. However, soft hands are petting his hair, a quiet voice is telling him how well he’s done, and someone is moving around enough that the bed dips with their weight. Worries allayed before he could even really begin to consider them, all he can see is Felix’s tear-streaked face. He’s beautiful, and the tiny, pleasured smile on his lips seems permanently etched. 

Felix meets Dimitri’s gaze, all wide-blown pupils and heaving breath, and says, eloquently, “fuck.”

Byleth and Marianne dissolve into giggles. A formless time passes where Dimitri only exists in terms of sensation. Felix is freed from his bonds, and Byleth rubs his wrists and ankles. He wraps one of his now-loose arms around Dimitri’s waist and presses their fronts together, nestling his face against Dimitri’s chest with a small, satisfied sound. Dimitri, perforce, wraps his arm around Felix in return, and gets a kiss from both women for it. Someone pulls a blanket up over them just before the cooling sweat and.. other fluids on their bodies become uncomfortable. He’s warm, and the bed is so soft, and he’s very tired after a full day’s work and what followed. His eye closes despite his best efforts, and even the world of sensation ceases to exist. 

Eventually, he returns to reality. Felix is still pressed into his chest, sleeping as quietly as he always has, and the sound of female voices drifts like soft music from another room. Dimitri realizes Marianne and Byleth must’ve gone out into the parlor, and lifts his head to glance around. The ropes are bundled neatly at the foot of the bed, his clothes and Felix’s are laid out on one of the vacant chairs, and there are two glasses of water on the bedside table. Feeling warmed by the consideration, Dimitri relaxes back into the embrace of the body next to him. 

Cuddling Felix is about how he expected it to be; a sharp hip pokes him in the stomach, a knee is digging into his thigh, Felix’s breath is sort of damp against his shoulder, and he wouldn’t change any part of it for the world. Dimitri is flooded by how much he cares for the man in his arms, and the revelation seems earthshaking. But Marianne knows already. She must, or she wouldn’t have conspired with Byleth to set this up. Byleth, therefore, must also know. 

Their wives seemed alright with the idea, though Dimitri is still worried about discovering the seedling feelings he’d buried long ago. They hadn’t died, like he’d expected them to. Instead, they’d grown, watered by time and fed by friendship, into a massive tree. Panic grips him like an icy claw in his chest at the thought that Felix might not be feeling the same; that this might have just been physical for him. After all, Byleth had told him they’d done this before, with several other couples. Sex clearly doesn’t mean the same thing to them as it does to him. He’d been a virgin before marrying Marianne, and had never forsaken his marriage bed. What if-

“You’re thinking too much,” a gravelly voice informs him. 

Dimitri looks down. Felix is staring at him, still half-asleep, hair sticking to his face on one side and looking entirely too adorable. Dimitri’s heart squeezes. 

“Quit looking at me like that,” Felix grumbles. He makes no move to squirm away. “I can see you freaking out. By already told you not to.”

“There are some things she did not know,” Dimitri protests, keeping his voice to a quiet rumble. 

Felix rolls his eyes. “Yeah, she did. She’s known how we feel about each other since the academy.”

“How _we_ feel-” Dimitri chokes himself off, not daring to hope. 

The look he gets for that one is pure Felix; sass and irritation vying for ascendency. “Shut up. Don’t make me say it.”

“Felix, I need you to be clear,” Dimitri insists. 

Felix groans and presses his face back into Dimitri’s chest. “Fine. I love you. Now shut up and let me rest. I don’t get fucked like that every day, you know.”

“Felix!”

“I said shut up.”

Dimitri can hardly contain his joy, but he manages it. He tightens his arm slightly, Felix grumbles at him, and he leans back into the softness of the bed. The sound of laughter from the other room lulls him to sleep.


End file.
